Next time some "alternative medicine" (ie anti-medicine) guru poses as a courageous maverick, remember: "Most mavericks are simply deluded and wrong." The co-author dream team of pop-science master Singh and "the world's first professor of complementary medicine", Ernst, explain in detail the history and scientific evidence (or lack thereof) for acupuncture, homeopathy, chiropractic and herbal medicine; and there is a handy Appendix for amusing dismissals of other fads such as ear candles or craniosacral therapy.

The results: acupuncture might be good for some pain and nausea but little else (and as better "fake" acupuncture for controlled trials is developed, the evidence seems to weaken further). A few herbs look OK for very specific conditions, chiropractic does nothing except maybe for your spine (but it might sever your arteries), and homeopathy is balls. The book covers much the same ground as Rose Shapiro's excellent recent Suckers, though it is a bit more long-winded and suffers from artificial injections of suspense. Perhaps most useful are its lucid explanations of the principles of controlled trials, meta-analyses and "evidence-based medicine" - all the institutions that show which treatments actually work, and so are despised by those who prey on the ignorant sick.

Lest you think the above means you can happily munch on your FDA-approved industrial pills, Stan Cox (an agricultural scientist) brings bad news. There is a burgeoning culture of "excessive testing", "disease-mongering" (medicalisation of non-medical problems), and other profiteering healthcare practices, which lead to more environmental degradation; meanwhile, the production of drug precursors in India causes appalling pollution that blights the health of Indians in order to help Americans concentrate in class or get erections.

If everyone took fish-oil capsules and drank green tea, we'd end up with dead oceans and rampant soil erosion. If "agroterrorists" attacked America's food supply, they could hardly poison and pollute any more than the agribusiness and chemical corporations already do routinely. Cox also explains the role of fossil fuels in agriculture, and insists that energy "efficiency" is not the answer to global warming, since it will lead to increased energy use. His ecological solution is to abandon capitalism completely. A radical treatment proposal, to be sure, but the diagnosis is sobering.

On Guerrilla Gardening, by Richard Reynolds (Bloomsbury, £14.99)

While consuming our way inevitably to the apocalypse, we can at least grow a few more pretty plants along the way, on neglected verges or urban roundabouts. To follow Cox's Kantian style: if everyone did it, the planet really would look a lot nicer (as well as soaking up a bit more carbon). Guerrilla gardening, Reynolds explains, is "the illicit cultivation of someone else's land", and this lovely book (with beautiful colour photographs of rebel flowers in grimy cities) is both a celebration of the international movement's recent history, and a how-to manual that advises on hardy species, planting techniques (including "seed-bombing") and social engineering.